Autocomplete producing MallocStackLogging exception message on user CLI

### Checks

- [x] I have searched [github.com/aws/amazon-q-developer-cli/issues](https://github.com/aws/amazon-q-developer-cli/issues?q=) and there are no duplicates of my issue
- [x] I have run `q doctor` in the affected terminal session
- [x] I have run `q restart` and replicated the issue again

### Operating system

macOS 15.3.2 (24D81)

### Expected behaviour

Expected: Autocomplete provides helpful selections or none at all

### Actual behaviour

I am seeing an autocomplete bug where I get an error message

`zsh (qterm)(8142) MallocStackLogging: can't turn off malloc stack logging because it was not enabled.`

when I cycle to last command with up arrow followed by pressing space

https://github.com/user-attachments/assets/ee74ce74-b83f-470f-846d-9957e7347542

### Steps to reproduce

Not sure. This happens intermittently, but multiple times by now (at least 5).

Notably, I had my mac yell at me that it was out of memory just before this happened - I had some rogue processes sucking up my memory (possibly related).

But when this occurred, I had killed those processes and had memory again.

### Environment

```yaml
[q-details]
version = "1.7.2"
hash = "b6bf5f1675dd7395009e8bc65c1145820671f211"
date = "2025-03-21T01:36:16.66764Z (8d ago)"
variant = "full"

[system-info]
os = "macOS 15.3.2 (24D81)"
chip = "Apple M1 Pro"
total-cores = 10
memory = "32.00 GB"

[environment]
cwd = "/Users/USER/Work/Fjord/S3ObjectPlannerService_S3AuthApi/src/S3ObjectPlannerContainer"
cli-path = "/Users/USER/Work/Fjord/S3ObjectPlannerService_S3AuthApi/src/S3ObjectPlannerContainer"
os = "Mac"
shell-path = "/bin/zsh"
shell-version = "5.9"
terminal = "iTerm 2"
install-method = "unknown"

[env-vars]
PATH = "/Users/USER/.local/share/mise/installs/node/20.18.2/bin:/opt/homebrew/opt/sqlite/bin:/opt/homebrew/opt/protobuf@3/bin:/usr/local/gnat/bin:/usr/local/opt/openssl@1.1/bin:/usr/local/opt/python/libexec/bin:/Users/USER/.rbenv/shims:/opt/homebrew/bin:/Users/USER/.nvm/versions/node/v8.17.0/bin:/opt/homebrew/bin:/opt/homebrew/sbin:/usr/local/bin/:/bin:/sbin:/usr/bin:/usr/local/sbin:/usr/local/bin:/Users/USER/.toolbox/bin:/Users/USER/bin:/opt/homebrew/opt/sqlite/bin:/opt/homebrew/opt/protobuf@3/bin:/usr/local/gnat/bin:/usr/local/opt/openssl@1.1/bin:/usr/local/opt/python/libexec/bin:/Users/USER/.rbenv/shims:/Users/USER/.nvm/versions/node/v8.17.0/bin:/System/Cryptexes/App/usr/bin:/usr/sbin:/var/run/com.apple.security.cryptexd/codex.system/bootstrap/usr/local/bin:/var/run/com.apple.security.cryptexd/codex.system/bootstrap/usr/bin:/var/run/com.apple.security.cryptexd/codex.system/bootstrap/usr/appleinternal/bin:/Users/USER/.cargo/bin:/Applications/iTerm.app/Contents/Resources/utilities:/Users/USER/.local/bin:/Users/USER/.odin-tools/env/OdinRetrievalScript-1.0/runtime/bin:/Users/USER/Work/EbsCLIMechanicWrapper/src/EbsCLIMechanicWrapper/src/ebs_cli_mechanic_wrapper:/Users/USER/Work/EbsCLIMechanicWrapper/src/EbsCLIMechanicWrapper/src:/Users/USER/Work/Tools:/Users/USER/Work/Tools/genai:/Users/USER/Work/Tools/genai/maxis:/Users/USER/Applications/IntelliJ IDEA Ultimate.app/Contents/MacOS"
QTERM_SESSION_ID = "18eecd05fd234dd3a645b58efa77c8a8"
Q_SET_PARENT_CHECK = "1"
Q_TERM = "1.7.2"
SHELL = "/bin/zsh"
TERM = "xterm-256color"
__CFBundleIdentifier = "com.googlecode.iterm2"
```

まず、説明されている上矢印とスペースのシーケンスに従って、macOS の zsh 上で q 1.7.2 の断続的なオートコンプリート失敗を再現します。q CLI のオートコンプリート経路を追跡し、MallocStackLogging メッセージが出力されるかどうかを確認します。オートコンプリートが例外なしで有用な選択肢、または選択肢なしを返せば完了です。

索引モデルが issue の本文から書いたものです。